Secondary cell group selection based on primary frequency band measurements

ABSTRACT

A method of wireless communication by a user equipment (UE) may include receiving a message requesting estimated channel characteristics of a secondary band based on measuring characteristics of a channel in the primary band. The method also includes measuring characteristics of the channel in the primary band. The method estimates channel characteristics of the secondary band based on the primary band characteristics measurements. The estimating may occur without measuring signals in the secondary band. Further, the method may report the estimated channel characteristics of the secondary band and receive an indication of a secondary cell group, based on the estimated channel characteristics of the secondary band.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. Provisional Patent Application No. 62/968,965, filed on Jan. 31, 2020, and titled “SECONDARY CELL GROUP SELECTION BASED ON PRIMARY FREQUENCY BAND MEASUREMENTS,” the disclosure of which is expressly incorporated by reference herein in its entirety.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication, and more particularly to techniques and apparatuses for efficient cell measurement to enable, for example, secondary cell selection.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and long term evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the universal mobile telecommunications system (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs). A user equipment (UE) may communicate with a base station (BS) via the downlink and uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail, a BS may be referred to as a Node B, a gNB, an access point (AP), a radio head, a transmit receive point (TRP), a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. New Radio (NR), which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP). NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink (UL), as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in NR and LTE technologies. Preferably, these improvements should be applicable to other multiple access technologies and the telecommunication standards that employ these technologies.

Artificial neural networks may comprise interconnected groups of artificial neurons (e.g., neuron models). The artificial neural network may be a computational device or represented as a method to be performed by a computational device. Convolutional neural networks, such as deep convolutional neural networks, are a type of feed-forward artificial neural network. Convolutional neural networks may include layers of neurons that may be configured in a tiled receptive field. It would be desirable to apply neural networking processing to wireless communications to achieve greater efficiencies.

SUMMARY

In some aspects of the present disclosure, a method of wireless communication by a user equipment (UE) may include receiving a message requesting estimated channel characteristics of a secondary band based on measuring characteristics of a channel in the primary band. The method may also include measuring characteristics of the channel in the primary band and estimating the channel characteristics of the secondary band without measuring signals in the secondary band. Further, the method may include reporting the estimated channel characteristics of the secondary band. A secondary cell group may be selected based on the estimated channel characteristics.

In some aspects, a method of wireless communication by a base station includes configuring a user equipment (UE) to estimate channel characteristics for a secondary band based on actual measurements of a primary band. The method may also include configuring reporting of the estimated channel characteristics. The method may further include selecting a secondary cell group (SCG) based on the reported estimated channel characteristics rather than secondary channel measurements.

A user equipment (UE) for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may receive a message requesting estimated channel characteristics of a secondary band based on measuring characteristics of a channel in the primary band. The UE may also measure characteristics of the channel in the primary band and estimate the channel characteristics of the secondary band without measuring signals in the secondary band. Further, the UE may report the estimated channel characteristics of the secondary band. A secondary cell group may be selected based on the estimated channel characteristics.

A base station for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may configure a user equipment (UE) to estimate channel characteristics for a secondary band based on actual measurements of a primary band. The base station may also configure reporting of the estimated channel characteristics. The base station may further select a secondary cell group (SCG) based on the reported estimated channel characteristics rather than secondary channel measurements.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and processing system as substantially described with reference to and as illustrated by the accompanying drawings and specification.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.

FIG. 1 is a block diagram conceptually illustrating an example of a wireless communication network, in accordance with various aspects of the present disclosure.

FIG. 2 is a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless communication network, in accordance with various aspects of the present disclosure.

FIG. 3 illustrates an example implementation of designing a neural network using a system-on-a-chip (SOC), including a general-purpose processor in accordance with certain aspects of the present disclosure.

FIGS. 4A, 4B, and 4C are diagrams illustrating a neural network in accordance with aspects of the present disclosure.

FIG. 4D is a diagram illustrating an exemplary deep convolutional network (DCN) in accordance with aspects of the present disclosure.

FIG. 5 is a block diagram illustrating an exemplary deep convolutional network (DCN) in accordance with aspects of the present disclosure.

FIG. 6 is a call flow diagram illustrating an example secondary cell group selection process, in accordance with various aspects of the present disclosure.

FIG. 7 is a flow diagram illustrating an example secondary band reporting process performed, for example, by a user equipment, in accordance with various aspects of the present disclosure.

FIG. 8 is a flow diagram illustrating an example secondary cell group selection process performed, for example, by a base station, in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully below with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth. In addition, the scope of the disclosure is intended to cover such an apparatus or method, which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth. It should be understood that any aspect of the disclosure disclosed may be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and/or the like (collectively referred to as “elements”). These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

It should be noted that while aspects may be described using terminology commonly associated with 5G and later wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as and including 3G and/or 4G technologies.

User equipments (UEs) may have the ability to operate in a dual connectivity (DC) mode. Dual connectivity allows a UE to simultaneously transmit and receive data on multiple bands with multiple cell groups including a master cell group and one or more secondary cell groups. In some configurations, the master cell group is based on a first radio access technology (RAT), such as LTE, and the secondary cell group is based on a secondary RAT, such as new radio (NR).

A base station may select a secondary cell group based on measurements from the UE. The measurements indicate a best frequency band from the UE's perspective, for example, based on measured reference signal received power (RSRP) of various secondary cell group frequency bands.

Machine learning techniques have been utilized to predict channel characteristics in a second band based on measurements in a first band, although RSRP is generally not predicted. The environment for both bands will be the same (or at least similar) because the propagation channels for each band are similar. It may be the case where measurement of the first band, for example frequency range one (FR1) is easier, cheaper, and/or more power efficient for the UE, than measuring the second band. For example, specific hardware characteristics of frequency range two (FR2) may make FR2 measurements less power efficient for a UE. Moreover, omitting measurements of a second band removes or at least reduces measurement overhead in the second band for reference signals. That is, the UE need not detect reference signals in the second band if measurements can be omitted. In other scenarios, a periodicity of the reference signals may be reduced in the second band.

According to aspects of the present disclosure, a UE performs measurements in a primary band, and then predicts and reports to a base station predicted characteristics of a secondary band based on the first band measurements. The base station selects a secondary cell group based on the predicted characteristics of the secondary band.

FIG. 1 is a diagram illustrating a network 100 in which aspects of the present disclosure may be practiced. The network 100 may be a 5G or NR network or some other wireless network, such as an LTE network. Wireless network 100 may include a number of BSs 110 (shown as BS 110 a, BS 110 b, BS 110 c, and BS 110 d) and other network entities. A BS is an entity that communicates with user equipment (UEs) and may also be referred to as a base station, a NR BS, a Node B, a gNB, a 5G node B (NB), an access point, a transmit receive point (TRP), and/or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG)). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in FIG. 1 , a BS 110 a may be a macro BS for a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102 b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS may support one or multiple (e.g., three) cells. The terms “eNB”, “base station”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” may be used interchangeably.

In some aspects, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the access network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.

Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in FIG. 1 , a relay station 110 d may communicate with macro BS 110 a and a UE 120 d in order to facilitate communication between BS 110 a and UE 120 d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impact on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 Watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 Watts).

A network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. Network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, and/or the like. A UE may be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or a satellite radio), a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, another device (e.g., remote device), or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE). UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120 e) may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another). For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like), a mesh network, and/or the like. In this case, the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere as being performed by the base station 110.

As indicated above, FIG. 1 is provided merely as an example. Other examples may differ from what is described with regard to FIG. 1 .

FIG. 2 shows a block diagram of a design 200 of base station 110 and UE 120, which may be one of the base stations and one of the UEs in FIG. 1 . Base station 110 may be equipped with T antennas 234 a through 234 t, and UE 120 may be equipped with R antennas 252 a through 252 r, where in general T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS(s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., the cell-specific reference signal (CRS)) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232 a through 232 t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232 a through 232 t may be transmitted via T antennas 234 a through 234 t, respectively. According to various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254 a through 254 r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254 a through 254 r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. A channel processor may determine reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), and/or the like. In some aspects, one or more components of UE 120 may be included in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254 a through 254 r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to base station 110. At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 254, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Network controller 130 may include communication unit 294, controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component(s) of FIG. 2 may perform one or more techniques associated with reporting estimated channel characteristics, for example, for secondary cell group selection, as described in more detail elsewhere. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component(s) of FIG. 2 may perform or direct operations of, for example, the process 600 of FIG. 6 and/or other processes as described. Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, UE 120 may include means for receiving, means for measuring, means for estimating, means for reporting, means for configuring, means for removing, and means for selecting. Such means may include one or more components of the UE 120 or base station 110 described in connection with FIG. 2 .

As indicated above, FIG. 2 is provided merely as an example. Other examples may differ from what is described with regard to FIG. 2 .

In some cases, different types of devices supporting different types of applications and/or services may coexist in a cell. Examples of different types of devices include UE handsets, Customer Premises Equipment (CPEs), vehicles, Internet of Things (IoT) devices, and/or the like. Examples of different types of applications include ultra-reliable low-latency communication (URLLC) applications, massive machine-type communication (mMTC) applications, enhanced mobile broadband (eMBB) applications, vehicle-to-anything (V2X) applications, and/or the like. Furthermore, in some cases, a single device may support different applications or services simultaneously.

FIG. 3 illustrates an example implementation of a system-on-a-chip (SOC) 300, which may include a central processing unit (CPU) 302 or a multi-core CPU configured for secondary cell group selection, in accordance with certain aspects of the present disclosure. The SOC 300 may be included in the base station 110 or UE 120. Variables (e.g., neural signals and synaptic weights), system parameters associated with a computational device (e.g., neural network with weights), delays, frequency bin information, and task information may be stored in a memory block associated with a neural processing unit (NPU) 108, in a memory block associated with a CPU 302, in a memory block associated with a graphics processing unit (GPU) 304, in a memory block associated with a digital signal processor (DSP) 306, in a memory block 318, or may be distributed across multiple blocks. Instructions executed at the CPU 302 may be loaded from a program memory associated with the CPU 302 or may be loaded from a memory block 318.

The SOC 300 may also include additional processing blocks tailored to specific functions, such as a GPU 304, a DSP 306, a connectivity block 310, which may include fifth generation (5G) connectivity, fourth generation long term evolution (4G LTE) connectivity, Wi-Fi connectivity, USB connectivity, Bluetooth connectivity, and the like, and a multimedia processor 312 that may, for example, detect and recognize gestures. In one implementation, the NPU is implemented in the CPU, DSP, and/or GPU. The SOC 300 may also include a sensor processor 314, image signal processors (ISPs) 316, and/or navigation module 320, which may include a global positioning system.

The SOC 300 may be based on an ARM instruction set. In an aspect of the present disclosure, the instructions loaded into the general-purpose processor 302 may comprise code to receive a message requesting estimated channel characteristics of a secondary band based on measuring of characteristics of a channel in a primary band. The general-purpose processor 302 may also comprise code to measure characteristics of the channel in the primary band. The general-purpose processor 302 may also comprise code to estimate channel characteristics of a secondary band without measuring signals in the secondary band. The general-purpose processor 302 may further comprise code to report the estimated channel characteristics of the secondary band. In other aspects of the present disclosure, the general-purpose processor 302 may comprises code to configure a user equipment (UE) to estimate channel characteristics for a secondary band based on measurements of a primary band. The general-purpose processor 302 may further comprise code to configure reporting of the estimated channel characteristics. The general-purpose processor 302 may further comprise code to select a secondary cell group (SCG) based on the estimated channel characteristics rather than secondary channel measurements.

Deep learning architectures may perform an object recognition task by learning to represent inputs at successively higher levels of abstraction in each layer, thereby building up a useful feature representation of the input data. In this way, deep learning addresses a major bottleneck of traditional machine learning. Prior to the advent of deep learning, a machine learning approach to an object recognition problem may have relied heavily on human engineered features, perhaps in combination with a shallow classifier. A shallow classifier may be a two-class linear classifier, for example, in which a weighted sum of the feature vector components may be compared with a threshold to predict to which class the input belongs. Human engineered features may be templates or kernels tailored to a specific problem domain by engineers with domain expertise. Deep learning architectures, in contrast, may learn to represent features that are similar to what a human engineer might design, but through training. Furthermore, a deep network may learn to represent and recognize new types of features that a human might not have considered.

A deep learning architecture may learn a hierarchy of features. If presented with visual data, for example, the first layer may learn to recognize relatively simple features, such as edges, in the input stream. In another example, if presented with auditory data, the first layer may learn to recognize spectral power in specific frequencies. The second layer, taking the output of the first layer as input, may learn to recognize combinations of features, such as simple shapes for visual data or combinations of sounds for auditory data. For instance, higher layers may learn to represent complex shapes in visual data or words in auditory data. Still higher layers may learn to recognize common visual objects or spoken phrases.

Deep learning architectures may perform especially well when applied to problems that have a natural hierarchical structure. For example, the classification of motorized vehicles may benefit from first learning to recognize wheels, windshields, and other features. These features may be combined at higher layers in different ways to recognize cars, trucks, and airplanes.

Neural networks may be designed with a variety of connectivity patterns. In feed-forward networks, information is passed from lower to higher layers, with each neuron in a given layer communicating to neurons in higher layers. A hierarchical representation may be built up in successive layers of a feed-forward network, as described above. Neural networks may also have recurrent or feedback (also called top-down) connections. In a recurrent connection, the output from a neuron in a given layer may be communicated to another neuron in the same layer. A recurrent architecture may be helpful in recognizing patterns that span more than one of the input data chunks that are delivered to the neural network in a sequence. A connection from a neuron in a given layer to a neuron in a lower layer is called a feedback (or top-down) connection. A network with many feedback connections may be helpful when the recognition of a high-level concept may aid in discriminating the particular low-level features of an input.

The connections between layers of a neural network may be fully connected or locally connected. FIG. 4A illustrates an example of a fully connected neural network 402. In a fully connected neural network 402, a neuron in a first layer may communicate its output to every neuron in a second layer, so that each neuron in the second layer will receive input from every neuron in the first layer. FIG. 4B illustrates an example of a locally connected neural network 404. In a locally connected neural network 404, a neuron in a first layer may be connected to a limited number of neurons in the second layer. More generally, a locally connected layer of the locally connected neural network 404 may be configured so that each neuron in a layer will have the same or a similar connectivity pattern, but with connections strengths that may have different values (e.g., 410, 412, 414, and 416). The locally connected connectivity pattern may give rise to spatially distinct receptive fields in a higher layer, because the higher layer neurons in a given region may receive inputs that are tuned through training to the properties of a restricted portion of the total input to the network.

One example of a locally connected neural network is a convolutional neural network. FIG. 4C illustrates an example of a convolutional neural network 406. The convolutional neural network 406 may be configured such that the connection strengths associated with the inputs for each neuron in the second layer are shared (e.g., 408). Convolutional neural networks may be well suited to problems in which the spatial location of inputs is meaningful.

One type of convolutional neural network is a deep convolutional network (DCN). FIG. 4D illustrates a detailed example of a DCN 400 designed to recognize visual features from an image 426 input from an image capturing device 430, such as a car-mounted camera. The DCN 400 of the current example may be trained to identify traffic signs and a number provided on the traffic sign. Of course, the DCN 400 may be trained for other tasks, such as identifying lane markings or identifying traffic lights.

The DCN 400 may be trained with supervised learning. During training, the DCN 400 may be presented with an image, such as the image 426 of a speed limit sign, and a forward pass may then be computed to produce an output 422. The DCN 400 may include a feature extraction section and a classification section. Upon receiving the image 426, a convolutional layer 432 may apply convolutional kernels (not shown) to the image 426 to generate a first set of feature maps 418. As an example, the convolutional kernel for the convolutional layer 432 may be a 5×5 kernel that generates 28×28 feature maps. In the present example, because four different feature maps are generated in the first set of feature maps 418, four different convolutional kernels were applied to the image 426 at the convolutional layer 432. The convolutional kernels may also be referred to as filters or convolutional filters.

The first set of feature maps 418 may be subsampled by a max pooling layer (not shown) to generate a second set of feature maps 420. The max pooling layer reduces the size of the first set of feature maps 418. That is, a size of the second set of feature maps 420, such as 14×14, is less than the size of the first set of feature maps 418, such as 28×28. The reduced size provides similar information to a subsequent layer while reducing memory consumption. The second set of feature maps 420 may be further convolved via one or more subsequent convolutional layers (not shown) to generate one or more subsequent sets of feature maps (not shown).

In the example of FIG. 4D, the second set of feature maps 420 is convolved to generate a first feature vector 424. Furthermore, the first feature vector 424 is further convolved to generate a second feature vector 428. Each feature of the second feature vector 428 may include a number that corresponds to a possible feature of the image 426, such as “sign,” “60,” and “100.” A softmax function (not shown) may convert the numbers in the second feature vector 428 to a probability. As such, an output 422 of the DCN 400 is a probability of the image 426 including one or more features.

In the present example, the probabilities in the output 422 for “sign” and “60” are higher than the probabilities of the others of the output 422, such as “30,” “40,” “50,” “70,” “80,” “90,” and “100”. Before training, the output 422 produced by the DCN 400 is likely to be incorrect. Thus, an error may be calculated between the output 422 and a target output. The target output is the ground truth of the image 426 (e.g., “sign” and “60”). The weights of the DCN 400 may then be adjusted so the output 422 of the DCN 400 is more closely aligned with the target output.

To adjust the weights, a learning algorithm may compute a gradient vector for the weights. The gradient may indicate an amount that an error would increase or decrease if the weight were adjusted. At the top layer, the gradient may correspond directly to the value of a weight connecting an activated neuron in the penultimate layer and a neuron in the output layer. In lower layers, the gradient may depend on the value of the weights and on the computed error gradients of the higher layers. The weights may then be adjusted to reduce the error. This manner of adjusting the weights may be referred to as “back propagation” as it involves a “backward pass” through the neural network.

In practice, the error gradient of weights may be calculated over a small number of examples, so that the calculated gradient approximates the true error gradient. This approximation method may be referred to as stochastic gradient descent. Stochastic gradient descent may be repeated until the achievable error rate of the entire system has stopped decreasing or until the error rate has reached a target level. After learning, the DCN may be presented with new images (e.g., the speed limit sign of the image 426) and a forward pass through the network may yield an output 422 that may be considered an inference or a prediction of the DCN.

Deep belief networks (DBNs) are probabilistic models comprising multiple layers of hidden nodes. DBNs may be used to extract a hierarchical representation of training data sets. A DBN may be obtained by stacking up layers of Restricted Boltzmann Machines (RBMs). An RBM is a type of artificial neural network that can learn a probability distribution over a set of inputs. Because RBMs can learn a probability distribution in the absence of information about the class to which each input should be categorized, RBMs are often used in unsupervised learning. Using a hybrid unsupervised and supervised paradigm, the bottom RBMs of a DBN may be trained in an unsupervised manner and may serve as feature extractors, and the top RBM may be trained in a supervised manner (on a joint distribution of inputs from the previous layer and target classes) and may serve as a classifier.

Deep convolutional networks (DCNs) are networks of convolutional networks, configured with additional pooling and normalization layers. DCNs have achieved state-of-the-art performance on many tasks. DCNs can be trained using supervised learning in which both the input and output targets are known for many exemplars and are used to modify the weights of the network by use of gradient descent methods.

DCNs may be feed-forward networks. In addition, as described above, the connections from a neuron in a first layer of a DCN to a group of neurons in the next higher layer are shared across the neurons in the first layer. The feed-forward and shared connections of DCNs may be exploited for fast processing. The computational burden of a DCN may be much less, for example, than that of a similarly sized neural network that comprises recurrent or feedback connections.

The processing of each layer of a convolutional network may be considered a spatially invariant template or basis projection. If the input is first decomposed into multiple channels, such as the red, green, and blue channels of a color image, then the convolutional network trained on that input may be considered three-dimensional, with two spatial dimensions along the axes of the image and a third dimension capturing color information. The outputs of the convolutional connections may be considered to form a feature map in the subsequent layer, with each element of the feature map (e.g., 220) receiving input from a range of neurons in the previous layer (e.g., feature maps 218) and from each of the multiple channels. The values in the feature map may be further processed with a non-linearity, such as a rectification, max(0, x). Values from adjacent neurons may be further pooled, which corresponds to down sampling, and may provide additional local invariance and dimensionality reduction. Normalization, which corresponds to whitening, may also be applied through lateral inhibition between neurons in the feature map.

The performance of deep learning architectures may increase as more labeled data points become available or as computational power increases. Modern deep neural networks are routinely trained with computing resources that are thousands of times greater than what was available to a typical researcher just fifteen years ago. New architectures and training paradigms may further boost the performance of deep learning. Rectified linear units may reduce a training issue known as vanishing gradients. New training techniques may reduce over-fitting and thus enable larger models to achieve better generalization. Encapsulation techniques may abstract data in a given receptive field and further boost overall performance.

FIG. 5 is a block diagram illustrating a deep convolutional network 550. The deep convolutional network 550 may include multiple different types of layers based on connectivity and weight sharing. As shown in FIG. 5 , the deep convolutional network 550 includes the convolution blocks 554A, 554B. Each of the convolution blocks 554A, 554B may be configured with a convolution layer (CONV) 356, a normalization layer (LNorm) 558, and a max pooling layer (MAX POOL) 560.

The convolution layers 556 may include one or more convolutional filters, which may be applied to the input data to generate a feature map. Although only two of the convolution blocks 554A, 554B are shown, the present disclosure is not so limiting, and instead, any number of the convolution blocks 554A, 554B may be included in the deep convolutional network 550 according to design preference. The normalization layer 558 may normalize the output of the convolution filters. For example, the normalization layer 558 may provide whitening or lateral inhibition. The max pooling layer 560 may provide down sampling aggregation over space for local invariance and dimensionality reduction.

The parallel filter banks, for example, of a deep convolutional network may be loaded on a CPU 302 or GPU 304 of an SOC 300 to achieve high performance and low power consumption. In alternative embodiments, the parallel filter banks may be loaded on the DSP 306 or an ISP 316 of an SOC 300. In addition, the deep convolutional network 550 may access other processing blocks that may be present on the SOC 300, such as sensor processor 314 and navigation module 320, dedicated, respectively, to sensors and navigation.

The deep convolutional network 550 may also include one or more fully connected layers 562 (FC1 and FC2). The deep convolutional network 550 may further include a logistic regression (LR) layer 564. Between each layer 556, 558, 560, 562, 564 of the deep convolutional network 550 are weights (not shown) that are to be updated. The output of each of the layers (e.g., 556, 558, 560, 562, 564) may serve as an input of a succeeding one of the layers (e.g., 556, 558, 560, 562, 564) in the deep convolutional network 550 to learn hierarchical feature representations from input data 552 (e.g., images, audio, video, sensor data and/or other input data) supplied at the first of the convolution blocks 554A. The output of the deep convolutional network 550 is a classification score 566 for the input data 552. The classification score 566 may be a set of probabilities, where each probability is the probability of the input data, including a feature from a set of features.

As indicated above, FIGS. 3-5 are provided as examples. Other examples may differ from what is described with respect to FIGS. 3-5 .

As described above, user equipments (UEs) may have the ability to operate in a dual connectivity (DC) mode. Dual connectivity allows a UE to simultaneously transmit and receive data on multiple bands with multiple cell groups including a master cell group and one or more secondary cell groups. In some configurations, the master cell group is based on a first radio access technology (RAT), such as LTE, and the secondary cell group is based on a secondary RAT, such as new radion (NR). The following description refers to these two radio access technologies, although other radio access technologies are possible for either cell group.

A base station may select a secondary cell group based on measurements from the UE. The measurements indicate a best frequency band from the UE's perspective, for example, based on measured reference signal received power (RSRP) of various NR frequency bands.

Machine learning techniques have been utilized to predict channel characteristics in a second band based on measurements in a first band, although RSRP is generally not predicted. The environment for both bands will be the same (or at least similar) because the propagation channels for each band are similar. It may be the case where measurement of the first band, for example frequency range one (FR1) is easier, cheaper, and/or more power efficient for the UE than measuring the second band. For example, specific hardware characteristics of frequency range two (FR2) may make FR2 measurements less power efficient for a UE. Moreover, omitting measurements of a second band removes or at least reduces measurement overhead in the second band for reference signals. That is, the UE need not detect reference signals in the second band if measurements can be omitted. In other scenarios, a periodicity of the reference signals may be reduced in the second band. According to aspects of the present disclosure, a UE performs measurements in a primary band, and then predicts and reports to a base station characteristics of a secondary band based on the first band measurements, enabling the base station to select a secondary cell group based on the predicted characteristics of the secondary band.

FIG. 6 is a call flow diagram illustrating an example secondary cell group selection process, in accordance with various aspects of the present disclosure. FIG. 7 is a flow diagram illustrating an example secondary band reporting process performed, for example, by a user equipment, in accordance with various aspects of the present disclosure. The example process 700 is an example of reporting estimated channel characteristics, for example, for secondary cell group selection based on measurements in a primary frequency band. In some aspects, the primary frequency band is lower than the secondary frequency band. For example the primary band may be below 6 GHz, and the secondary band may be above 20 GHz.

The process 700 may operate in a dual connectivity scenario in which new radio (NR) and LTE are deployed where a master cell 110 operates with LTE and a secondary cell 111 operates with NR. This scenario may be referred to as dual connectivity. The UE 120 initially connects to the master cell 110 in the LTE network, and subsequently connects to the secondary cell 111 in the NR network via an RRC Connection Reconfiguration process. In the dual connectivity examples of FIGS. 6 and 7 , the LTE base station 110 corresponds to the master cell group (MCG) and the NR base station 111 corresponds to the secondary cell group (SCG).

The UE 120 performs initial registration with the MCG 110 at time t0. The MCG 110 may add one or more SCGs 111, although only one SCG 111 is shown in FIG. 6 . In order to add a SCG 111, as shown in FIGS. 6 and 7 , the process 700 may include, at time t1, receiving a message requesting secondary band channel characteristic estimates based on characteristics of a channel in a primary band (block 705). For example a modified RRC Connection Reconfiguration message from the master base station 110 may configure a UE 120 to send channel characteristic estimates of the secondary band. The modified message may request estimated channel characteristics for the SCG 111. Either an extra report based on incumbent CSI-RS signaling or a new CSI-RS signal may be configured for reporting of the estimated channel characteristics. The UE 120 (e.g., using the antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller/processor 280, and or the like) may receive the message.

As shown in FIGS. 6 and 7 , in some aspects, the process 700 may include, at time t2, measuring characteristics of a channel in a primary band (block 710). For example, the UE 120 (e.g., using the antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller/processor 280, and or the like) may measure characteristics of the channel, for example an LTE sub 6 GHz band. Some examples of the measurements that the UE 120 may perform are reference signal receive power (RSRP) measurements in the first band, positioning information of the UE 120 (e.g., which may be used to learn the beam direction), raw channel measurements, channel impulse response (CIR) measurements, angle of departure (AoD) measurements (e.g., AoD of the strongest multi-path component (MPC)), delay profile of the strongest MPC, and/or other measurements in the first band. These measurements may be inputs to a machine learning algorithm.

As shown in FIGS. 6 and 7 , in some aspects, the process 700 may include, at time t3, estimating channel characteristics of a secondary band. The estimates may be a neural network prediction based on the primary band performance measurements. The estimating occurs without measuring signals in the secondary band (block 720). For example, the UE 120 (e.g., using the controller/processor 280, and or the like) can ignore any configuration for the secondary band (e.g., new radio (NR)) measurements and instead perform the estimating of the channel characteristics with artificial intelligence (AI).

As shown in FIGS. 6 and 7 , in some aspects, the process 700 may include, at time t4, reporting the estimated channel characteristics (block 730). For example, the UE 120 (e.g., using the antenna 252, MOD 254, TX MIMO detector 266, transmit processor 264, controller/processor 280, and or the like) may report the estimated channel characteristics instead of actual values for NR measurements. The reporting may be based on one of the types of CSI-RS signaling, as mentioned above. The reporting may also include a list of bands to which the estimated channel characteristics are applicable.

Optionally, as shown in FIGS. 6 and 7 , the process 700 may include, at time t5, receiving an indication of a secondary cell group, which was determined based on the estimated channel characteristics (block 740). For example, the master base station 110 determines the secondary cell group 111 based on the estimated report received from the UE 120, as well as status reports from secondary base stations. This determination by the master base station 110 is based on the estimated channel characteristics, instead of actual channel measurements. The UE 120 receives an indication from the master base station of the secondary cell group (SCG). The UE 120 receives the indication using e.g., the antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller/processor 280, and or the like. At time t6, the UE 120 connects to the secondary cell group 111.

FIG. 8 is a flow diagram illustrating an example secondary cell group selection process 800 performed, for example, by a base station, in accordance with various aspects of the present disclosure. The example process 800 is an example of configuring reporting estimated channel characteristics, for example, for secondary cell group selection based on measurements in a primary frequency band. As shown in FIG. 8 , in some aspects, the process 800 may include configuring a user equipment (UE) to estimate channel characteristics for a secondary band, for example with neural network processing of actual measurements of a primary band (block 810). The base station may configure the UE using the antenna 234, MOD 232, TX MIMO processor 230, transmit processor 220, controller/processor 240, and scheduler 246 and or the like.

As shown in FIG. 8 , in some aspects, the process 800 may include configuring reporting of the estimated channel characteristics (block 820). In some aspects, the master base station may configure a new report for estimated channel characteristics based on incumbent CSI-RS signals. Alternatively, the master base station may configure a new CSI-RS signal and a new corresponding report for the UE. The configuration may be through an RRC message, such as a RRCConnectionReconfiguration message. The base station may configure the UE using the antenna 234, MOD 232, TX MIMO processor 230, transmit processor 220, controller/processor 240, and scheduler 246 and or the like.

As shown in FIG. 8 , in some aspects, the process 800 may include selecting a secondary cell group (SCG) based on the estimated channel characteristics rather than actual secondary channel measurements (block 830). The base station selects the SCG using, e.g., the controller/processor 240, and or the like.

Although FIGS. 7 and 8 show example blocks of the processes 700, 800 in some aspects, the processes 700, 800 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in FIGS. 7 and 8 . Additionally, or alternatively, two or more of the blocks of the processes 700, 800 may be performed in parallel. Similarly, the processes shown in FIG. 6 may include additional processes, fewer processes, different processes, or differently arranged processes than those depicted in FIG. 6 . Two or more of the processes may be performed in parallel.

Implementation examples are described in the following numbered clauses.

-   -   1. A method of wireless communication by a user equipment (UE),         comprising:         -   receiving a message requesting estimated channel             characteristics of a secondary band based on measuring of             characteristics of a channel in a primary band;         -   measuring characteristics of the channel in the primary             band;         -   estimating channel characteristics of the secondary band             based on measured characteristics of the channel in the             primary band, the estimating occurring without measuring             signals in the secondary band; and         -   reporting the estimated channel characteristics of the             secondary band.     -   2. The method of clause 1, further comprising receiving an         indication of a secondary cell group, which was determined based         on the estimated channel characteristics of the secondary band.     -   3. The method of any of the preceding clauses, in which the         measured characteristics of the channel in the primary band are         measurements of signals transmitted by a non-serving cell.     -   4. The method of any of the preceding clauses, in which the         non-serving cell comprises a collocated first base station of a         first radio access technology (RAT) and a second base station of         a second RAT.     -   5. The method of any of the preceding clauses, further         comprising removing a potential secondary cell group from         consideration based on determining that estimated channel         characteristics of the potential secondary cell group are below         a threshold.     -   6. The method of any of the preceding clauses, in which         measuring characteristics of the channel in the primary band         comprises at least one of measuring reference signal received         power (RSRP) of the channel in the primary band, performing a         channel estimate of the channel in the primary band, measuring a         channel impulse response (CIR) of the channel in the primary         band, measuring an angle of departure of the channel in the         primary band, measuring an angle of arrival of the channel in         the primary band, measuring a channel path delay of the channel         in the primary band, determining a user equipment (UE) position,         and analyzing a power delay profile of the channel in the         primary band.     -   7. The method of any of the preceding clauses, further         comprising:         -   reporting the estimated channel characteristics of the             secondary band based on an existing channel state             information (CSI) signal and a report configuration received             from a master base station in a radio resource control (RRC)             message; and         -   reporting measurements of the characteristics of the channel             in the primary band based on the existing CSI signal.     -   8. The method of any of the preceding clauses, further         comprising:         -   reporting measurements of the characteristics of the channel             in the primary band based on a first type of channel state             information (CSI) signal; and         -   reporting the estimated channel characteristics of the             secondary band based on a second type of CSI signal and a             report configuration, which is received from a master base             station in a radio resource control (RRC) message and             corresponds to the second type of CSI signal.     -   9. The method of any of the preceding clauses, in which         reporting the estimated channel characteristics further         comprises reporting a list of bands to which the estimated         channel characteristics apply.     -   10. The method of any of the preceding clauses, in which the         primary band is lower in frequency than the secondary band.     -   11. The method of any of the preceding clauses, in which the         estimating channel characteristics of the secondary band is         performed with neural network processing.     -   12. A method of wireless communication by a base station,         comprising:         -   configuring a user equipment (UE) to estimate channel             characteristics of a secondary band based on measurements of             a primary band;         -   configuring reporting of the estimated channel             characteristics of the secondary band; and         -   selecting a secondary cell group (SCG) based on the             estimated channel characteristics of the secondary band             rather than measurements of the secondary band.     -   13. The method of clause 12, in which configuring reporting         comprises configuring a new report for estimated channel         characteristics of the secondary band based on incumbent channel         state information (CSI) signals.     -   14. The method of clause 12, in which configuring reporting         comprises configuring a new channel state information (CSI)         signal and a new corresponding report for the estimated channel         characteristics of the secondary band.     -   15. A user equipment (UE) for wireless communication comprising:         -   a memory, and         -   at least one processor operatively coupled to the memory,             the memory and the at least one processor configured:         -   to receive a message requesting estimated channel             characteristics of a secondary band based on measuring of             characteristics of a channel in a primary band;         -   to measure characteristics of the channel in the primary             band;         -   to estimate channel characteristics of the secondary band             based on measured characteristics of the channel in the             primary band, the estimating occurring without measuring             signals in the secondary band; and         -   to report the estimated channel characteristics of the             secondary band.     -   16. The UE of clause 15, in which the at least one processor is         further configured to receive an indication of a secondary cell         group, which was determined based on the estimated channel         characteristics.     -   17. The UE of any of the preceding clauses, in which the         measured characteristics of the channel in the primary band are         measurements of signals transmitted by a non-serving cell.     -   18. The UE of any of the preceding clauses, in which the         non-serving cell comprises a collocated first base station of a         first radio access technology (RAT) and a second base station of         a second RAT.     -   19. The UE of any of the preceding clauses, in which the at         least one processor is further configured to remove a potential         secondary cell group from consideration based on determining         that the estimated channel characteristics of the potential         secondary cell group are below a threshold.     -   20. The UE of any of the preceding clauses, in which the at         least one processor is further configured to measure         characteristics by at least one of measuring reference signal         received power (RSRP) of the channel in the primary band,         performing a channel estimate of the channel in the primary         band, measuring a channel impulse response (CIR) of the channel         in the primary band, measuring an angle of departure of the         channel in the primary band, measuring an angle of arrival of         the channel in the primary band, measuring a channel path delay         of the channel in the primary band, determining a user equipment         (UE) position, and analyzing a power delay profile of the of the         channel in the primary band.     -   21. The UE of any of the preceding clauses, in which the at         least one processor is further configured:         -   to report the estimated channel characteristics of the             secondary band based on an existing channel state             information (CSI) signal and a report configuration received             from a master base station in a radio resource configuration             (RRC) message; and         -   to report measurements of the characteristics of the channel             in the primary band based on the existing CSI signal.     -   22. The UE of any of the preceding clauses, in which the at         least one processor is further configured:         -   to report measurements of the characteristics of the channel             in the primary band based on a first type of channel state             information (CSI) signal; and         -   to report the estimated channel characteristics of the             secondary band based on a second type of CSI signal and a             report configuration, which is received from a master base             station in a radio resource control (RRC) message and             corresponds to the second type of CSI signal.     -   23. The UE of any of the preceding clauses, in which the at         least one processor is further configured to report the         estimated channel characteristics by reporting a list of bands         to which the estimated channel characteristics apply.     -   24. The UE of any of the preceding clauses, in which the primary         band is lower in frequency than the secondary band.     -   25. The UE of any of the preceding clauses, in which the at         least one processor is further configured to estimate with         neural network processing.     -   26. A base station for wireless communication comprising:         -   a memory, and         -   at least one processor operatively coupled to the memory,             the memory and the at least one processor configured:         -   to configure a user equipment (UE) to estimate channel             characteristics of a secondary band based on measurements of             a primary band;         -   to configure reporting of the estimated channel             characteristics of the secondary band; and         -   to select a secondary cell group (SCG) based on the             estimated channel characteristics of the secondary band             rather than measurements of the secondary band.     -   27. The base station of clause 26, in which the at least one         processor is further configured to configure a new report for         estimated channel characteristics of the secondary band based on         incumbent channel state information (CSI) signals.     -   28. The base station of clause 26, in which the at least one         processor is further configured to configure a new channel state         information (CSI) signal and a new corresponding report for the         estimated channel characteristics of the secondary band.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.

As used, the term “component” is intended to be broadly construed as hardware, firmware, and/or a combination of hardware and software. As used, a processor is implemented in hardware, firmware, and/or a combination of hardware and software.

Some aspects are described in connection with thresholds. As used, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

It will be apparent that systems and/or methods described may be implemented in different forms of hardware, firmware, and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described without reference to specific software code—it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c).

No element, act, or instruction used should be construed as critical or essential unless explicitly described as such. Also, as used, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more.” Furthermore, as used, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like), and may be used interchangeably with “one or more.” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used, the terms “has,” “have,” “having,” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. 

What is claimed is:
 1. A method of wireless communication by a user equipment (UE), comprising: estimating channel characteristics of a secondary band based on measured characteristics of a channel in a primary band, the estimating occurring without measuring signals in the secondary band, the primary band detected in signals received from a non-serving cell of a first radio access technology (RAT), the non-serving cell comprising a first base station of the first RAT that is collocated with a second base station of a second RAT; reporting, to a base station of a serving cell of the first RAT, the estimated channel characteristics of the secondary band; and receiving an indication of a secondary cell group, the secondary cell group determined based on the estimated channel characteristics of the secondary band.
 2. The method of claim 1, further comprising removing a potential secondary cell group from consideration upon determining that estimated channel characteristics of the potential secondary cell group are below a threshold.
 3. The method of claim 1, wherein the measurement of characteristics of the channel in the primary band further comprises at least one of measuring reference signal received power (RSRP) of the channel in the primary band, performing a channel estimate of the channel in the primary band, measuring a channel impulse response (CIR) of the channel in the primary band, measuring an angle of departure of the channel in the primary band, measuring an angle of arrival of the channel in the primary band, measuring a channel path delay of the channel in the primary band, determining a user equipment (UE) position, and analyzing a power delay profile of the channel in the primary band.
 4. The method of claim 1, further comprising: reporting the estimated channel characteristics of the secondary band based on measuring an existing channel state information (CSI) signal and a report configuration received from a master base station in a radio resource control (RRC) message; and reporting measurements of the characteristics of the channel in the primary band based on the existing CSI signal.
 5. The method of claim 1, further comprising: reporting measurements of the characteristics of the channel in the primary band based on measuring a first type of channel state information (CSI) signal; and reporting the estimated channel characteristics of the secondary band based on measuring a second type of CSI signal and a report configuration, which is received from a master base station in a radio resource control (RRC) message and corresponds to the second type of CSI signal.
 6. The method of claim 1, wherein reporting the estimated channel characteristics further comprises reporting a list of bands to which the estimated channel characteristics apply.
 7. The method of claim 1, wherein the primary band is lower in frequency than the secondary band.
 8. The method of claim 1, wherein estimating the channel characteristics of the secondary band is performed with neural network processing.
 9. A method of wireless communication by a base station, comprising: configuring a user equipment (UE) to estimate channel characteristics of a secondary band based on measurements of signals in a primary band received from a non-serving cell of a first radio access technology (RAT), the non-serving cell comprising a first base station of the first RAT that is collocated with a second base station of a second RAT; configuring reporting of the estimated channel characteristics of the secondary band; and selecting a secondary cell group (SCG) based on the estimated channel characteristics of the secondary band without using measurements of the secondary band.
 10. The method of claim 9, wherein configuring the reporting further comprises configuring a new report for estimated channel characteristics of the secondary band based on incumbent channel state information (CSI) signals.
 11. The method of claim 9, wherein configuring the reporting further comprises configuring a new channel state information (CSI) signal and a new corresponding report for the estimated channel characteristics of the secondary band.
 12. A user equipment (UE) for wireless communication comprising: a memory, and at least one processor operatively coupled to the memory, the memory and the at least one processor configured to: estimate channel characteristics of a secondary band based on measured characteristics of a channel in a primary band, the estimating occurring without measuring signals in the secondary band, the primary band detected in signals received from a non-serving cell of a first radio access technology (RAT), the non-serving cell comprising a first base station of the first RAT that is collocated with a second base station of a second RAT; report, to a base station of a serving cell of the first RAT, the estimated channel characteristics of the secondary band; and receive an indication of a secondary cell group, the secondary cell group determined based on the estimated channel characteristics of the secondary band.
 13. The UE of claim 12, wherein the at least one processor is further configured to remove a potential secondary cell group from consideration upon determining that the estimated channel characteristics of the potential secondary cell group are below a threshold.
 14. The UE of claim 12, wherein measurement of characteristics in the primary band further comprises at least one of: measuring reference signal received power (RSRP) of the channel in the primary band, performing a channel estimate of the channel in the primary band, measuring a channel impulse response (CIR) of the channel in the primary band, measuring an angle of departure of the channel in the primary band, measuring an angle of arrival of the channel in the primary band, measuring a channel path delay of the channel in the primary band, determining a user equipment (UE) position, and analyzing a power delay profile of the of the channel in the primary band.
 15. The UE of claim 12, wherein the at least one processor is further configured: to report the estimated channel characteristics of the secondary band based on measuring an existing channel state information (CSI) signal and a report configuration received from a master base station in a radio resource configuration (RRC) message; and to report measurements of the characteristics of the channel in the primary band based on measuring the existing CSI signal.
 16. The UE of claim 12, wherein the at least one processor is further configured: to report measurements of the characteristics of the channel in the primary band based on measuring a first type of channel state information (CSI) signal; and to report the estimated channel characteristics of the secondary band based on measuring a second type of CSI signal and a report configuration, which is received from a master base station in a radio resource control (RRC) message and corresponds to the second type of CSI signal.
 17. The UE of claim 12, wherein the at least one processor is further configured to report the estimated channel characteristics by reporting a list of bands to which the estimated channel characteristics apply.
 18. The UE of claim 12, wherein the primary band is lower in frequency than the secondary band.
 19. The UE of claim 12, wherein the at least one processor is further configured to estimate the channel characteristics of the secondary band with neural network processing.
 20. A base station for wireless communication comprising: a memory, and at least one processor operatively coupled to the memory, the memory and the at least one processor configured to: configure a user equipment (UE) to estimate channel characteristics of a secondary band based on measurements of signals in a primary band received from a non-serving cell of a first radio access technology (RAT), the non-serving cell comprising a first base station of the first RAT that is collocated with a second base station of a second RAT; configure reporting of the estimated channel characteristics of the secondary band; and select a secondary cell group (SCG) based on the estimated channel characteristics of the secondary band without using measurements of the secondary band.
 21. The base station of claim 20, wherein the at least one processor is further configured to configure a new report for estimated channel characteristics of the secondary band based on incumbent channel state information (CSI) signals.
 22. The base station of claim 20, wherein the at least one processor is further configured to configure a new channel state information (CSI) signal and a new corresponding report for the estimated channel characteristics of the secondary band. 